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Tropical theileriosis is an important protozoan tick-borne disease in cattle. Vaccination using attenuated schizont-infected cell lines is one of the methods used for controlling the disease. This study describes the production of attenuated schizont-infected cell lines from Egypt and an evaluation of its use as a vaccine to protect calves against clinical disease upon field challenge. Two groups of exotic and crossbred male calves were divided into vaccinated and control groups. The vaccinated groups were inoculated with 4 ml (1 × 106 cells/ml) of the attenuated cell line. Three weeks after vaccination, calves of both groups were transported to the New Valley Governorate (Egyptian oasis) where they were kept under field conditions and exposed to the natural Theileria annulata challenge. All animals in the control group showed severe clinical signs and died despite treatment with buparvaquone, which was administered after two days of persistent fever due to a severe drop in packed cell volume (PCV). Animals in the vaccinated group became seropositive without developing severe clinical signs other than transient fever. Post-mortem examinations revealed enlarged and fragile lymph nodes, spleen, and liver with necrosis and hemorrhages. These findings indicate that the Egyptian attenuated cell line was successful in protecting both exotic and crossbred animals against tropical theileriosis under field conditions. [ABSTRACT FROM AUTHOR]

The current work was carried out to reveal-up the probable cause that increases the seriousness of lumpy skin disease (LSD) in crossbred dairy cattle in villages of Assiut and Sohag Governorates, Upper Egypt. The serious form of LSD infected twenty-eight crossbred dairy cows. Diagnosis is based on the clinical background and histopathology. All cows were adult and previously vaccinated against LSD using the sheep pox "Romanian-strain" vaccine. Clinically, enormous numbers of hideous necrotic dermal lesions, similar to starred-shaped craters, were the prominent signs of the diseased cases in association with systemic reactions anorexia pyrexia, tachycardia, tachypnea, and edematous lymphadenitis in superficial nodes. Detailed clinical findings are described. Histopathologically, fibrinoid vasculitis, with severe perivascular mononuclear inflammatory cellular infiltration and ambulance of eosinophilic intracytoplasmic inclusions in the dermis were conspicuously histopathological findings. Blood films and lymph smears of the diseased cases revealed both erythrocytic and the lymphocytic forms of Theileria infection. Theileria annulata was identified by polymerase chain reaction (PCR). Theileria annulata infection and LSD interactions were discussed. This tick-borne-protozoan is an endemic infection in our villages and plays a pivotal role in the frustration of the humoral and cell-mediated immune statuses of the infected cattle inducing reduction of the efficiency of the applied vaccine, and increasing the seriousness of the endemic lumpy skin disease. A national strategy for reducing or minimizing the infection rate with Theileria infection should warranted in paralleling with vaccination programs to avoid the insufficiency of immune responses. The current work concludes that bovine theileriosis is an endemic disease in our villages and the existence of Theileria annulata infection minimizes the efficiency of the vaccination programs and increases the seriousness of LSD in crossbred cattle. The existence of sporadic cases of cattle infected by LSD precipitates the disease as a circulating disease in our villages in Egypt. [ABSTRACT FROM AUTHOR]

Background: Hemoprotozoan diseases, especially trypanosomosis and theileriosis, adversely affect the productivity, growth, and performance of camels. Regular sampling and investigation of camels are challenging due to several factors. Consequently, there is a lack of knowledge on camel parasite genotyping, cytokine production, and oxidative stress parameters during infection., Methods: The present study investigated two critical blood protozoa infecting camels in Egypt, Trypanosoma evansi and Theileria annulata, using molecular methods, specifically 18S rRNA gene analysis. Following molecular confirmation, experimental infections were induced in Swiss albino mice to assess the expression of immune response genes and oxidative stress parameters. The study further explored the correlation between histopathological alterations and inflammatory reactions in the kidney, spleen, and liver of infected mice, alongside the immunohistochemical expression of caspase-3, proliferating cell nuclear antigen (PCNA), and tumor necrosis factor (TNF)., Results: Trypanosoma evansi and T. annulata isolated from naturally infected camels were molecularly identified and deposited in GenBank under accession numbers OR116429 and OR103130, respectively. Infection with T. evansi and T. annulata caused significant adverse effects on the immune condition of infected mice, increasing the pathogenicity of the infection. This was evidenced by a significant increase in oxidative stress parameter levels in both naturally infected camels and experimentally infected mice compared to healthy controls. Furthermore, the expression of immune response genes was significantly elevated in infected mice. Immunohistochemistry analysis showed a pronounced upregulation of caspase-3, PCNA, and TNF in the infected groups relative to the control group. These findings are the first to be reported in Egypt., Conclusions: This study successfully identified and genotyped two economically important blood protozoa, T. evansi and T. annulata, from camels in Egypt. Additionally, the experimental animal model provided valuable insights into the immune response, oxidative stress, and histopathological changes induced by these parasites, demonstrating comparable results to naturally infected camels. These findings highlight the potential of this model to study parasite-host interactions and immune responses, contributing to a better understanding of the pathogenic mechanisms of T. evansi and T. annulata infections. This model may be useful for future studies focused on disease control and therapeutic interventions., Competing Interests: Declarations Ethics approval and consent to participate This study adhered to the principles of the Helsinki Declaration. The institutional review board of Cairo University's Institutional Animal Care and Use Ethical Committee (VET-CU 25122023815) approved the procedures for handling and collecting animal samples. The study was conducted at Cairo University's Faculty of Veterinary Medicine. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Background and Aim: Theileria annulata infection is a tick-borne disease affecting ruminants in the tropical and subtropical regions causing severe economic losses. This study aimed to characterize circulating T. annulata isolates from four governorates (administrative districts) north and south of Egypt using polymerase chain reaction (PCR)-restriction fragment length polymorphism. Materials and Methods: Fifty samples were collected from the four governorates of Egypt and were examined by a PCR assay based on the heat shock protein 70 gene. The amplified product was subsequently digested using two restriction enzymes, Taq I and Alu I, to determine which pattern of T. annulata strains was involved. Results: The findings revealed that one distinct pattern was observed for T. annulata isolates in the northern governorates and another one in the southern governorates. The Taq I enzyme produced three fragments (100, 175, and 270 bp), and the Alu I enzyme produced four fragments (60, 90, 125, and 270 bp). Conclusion: This study determined the presence of two distinct circulating genotypes of T. annulata among cattle in Egypt based on PCR-RFLP using the HSP 70 gene. More studies are needed in different parts of the country to investigate the virulence and strain variance of T. annulata in cattle. [ABSTRACT FROM AUTHOR]

Background and Aim: Theileria annulata is the most prevalent piroplasm infecting cattle across Egypt. Theileriosis is transmitted by ixodid ticks of the genus Hyalomma. This study aimed to estimate the prevalence of theileriosis in cattle and their associated risk factors for infection. Materials and Methods: A total of 570 blood samples were collected from cattle from five governorates (administrative districts) in Egypt and examined using a polymerase chain reaction assay to estimate the prevalence of tropical theileriosis and assess the associated risk factors. Results: The overall prevalence rate was 16.49%, with the Alexandria district having the highest prevalence. The results revealed that the risk of theileriosis was elevated in older cattle (odds ratio [OR]=8.9, 95% confidence interval [CI]: 3.6- 21.9), especially in summers (OR=3.07, 95% CI: 1.4-6.3). Cattle heavily infested with ticks were at particular risk (OR=3.05, 95% CI: 2.1-4.5), as were those to which acaricide had not been applied (OR=13.7, 95% CI: 5.6-33.6). Conclusion: Understanding the risk factors associated with T. annulata infection and regular infection monitoring could reduce infection rates and economic losses and is essential for the implementation of efficient control programs. [ABSTRACT FROM AUTHOR]

Background: Under the poor hygienic conditions, tick-borne pathogens cause severe economic losses to the cattle industry. Purpose: The current study investigated the presence of Theileria annulata, Babesia bigemina, and Anaplasma marginale, the most relevant tick-borne pathogens in cattle, in 3 provinces of Egypt utilizing species-specific PCR assays. Methods: PCR was conducted, on bovine blood specimens, using primers targeting the T. annulata merozoite–piroplasm surface antigen (Tams1, 768 bp), A. marginale major surface protein-1b gene (msp1b, 265 bp), and B. bigemina small subunit ribosomal RNA gene (SSrRNA, 543 bp). Results: PCR findings revealed overall prevalences of T. annulata, B. bigemina, and A. marginale as 22.0% (33/150), 19.33% (29/150), and 10.6% (16/150), respectively. The co-infection with two or three pathogens was detected in 20.0% (30/150) of examined specimens. Sequence analyses indicated that T. annulata and A. marginale varied from those of corresponding GenBank sequences revealing percent identities ranging from 90.68 to 97.75% and from 94.98 to 98.63%, respectively. On the other hand, the obtained B. bigemina sequences showed a high similarity with those previously reported in GenBank with a percent identity ranging from 98.85 to 100%. Conclusion: T. annulata was the most prevalent tick-borne pathogen in examined bovine specimens. The genetic diversity of markers used for identification of T. annulata and A. marginale should be highly considered. [ABSTRACT FROM AUTHOR]

Buparvaquone is now the principle medicinal drug utilized against tropical theileriosis. The current study was conducted to determine the potential association between the resistance against buparvaquone and the occurrence of mutations in the Cytochrome b (Cyto b) gene of Theileria annulata (T. annulata) in cattle under Egyptian conditions. We sequenced the Cyto b gene of T. annulata of 6 blood samples collected from 1 responding and 5 non-responding cattle to buparvaquone treatment. The analysis revealed that two mutations occurred in codons 253 and 262 within the quinol oxidation (Qo2) drug-binding site of the five resistant isolates. Two mutations in the Qo1 site were found together in the buparvaquone sensitive isolate only. Our findings suggest that the failure of buparvaquone therapy could be attributed to the presence of single or double point mutations at the Qo2 site of T. annulata Cyto b gene. [ABSTRACT FROM AUTHOR]